The nature of probability-measure languages (pm-languages) has been investigated [2], [3], [7], [8], in particular, those languages generated by given probabilistic grammars (p-grammars). However, the determination of a p-grammar that can generate some given language has been an open question. Since languages are infinite in general, the specification of a pm-language is vague. In this paper, it is assumed that some finite representation exists for the set of words (this can be a nonprobabilistic grammar) and that the probability of each word in the language is computable by some word function whose domain is the language.